U.S. patent application number 14/911790 was filed with the patent office on 2016-07-07 for systems and methods for supporting bollards.
This patent application is currently assigned to THE UAB RESEARCH FOUNDATION. The applicant listed for this patent is THE UAB RESEARCH FOUNDATION. Invention is credited to DAVID LITTLEFIELD, DEAN SICKING, KENNETH WALLS.
Application Number | 20160194841 14/911790 |
Document ID | / |
Family ID | 52468654 |
Filed Date | 2016-07-07 |
United States Patent
Application |
20160194841 |
Kind Code |
A1 |
SICKING; DEAN ; et
al. |
July 7, 2016 |
SYSTEMS AND METHODS FOR SUPPORTING BOLLARDS
Abstract
In one embodiment, a bollard system includes multiple support
beams adapted to be embedded in concrete, multiple bollards, each
bollard being attached to a support beam a point near a center of
the beam, and a reinforcing bar that is woven between the support
beams to provide reinforcement to the system.
Inventors: |
SICKING; DEAN; (INDIAN
SPRINGS VILLAGE, AL) ; LITTLEFIELD; DAVID; (VESTAVIA
HILLS, AL) ; WALLS; KENNETH; (MOODY, AL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
THE UAB RESEARCH FOUNDATION |
Birmingham |
AL |
US |
|
|
Assignee: |
THE UAB RESEARCH FOUNDATION
BIRMINGHAM
AL
|
Family ID: |
52468654 |
Appl. No.: |
14/911790 |
Filed: |
August 13, 2014 |
PCT Filed: |
August 13, 2014 |
PCT NO: |
PCT/US2014/050869 |
371 Date: |
February 12, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61865413 |
Aug 13, 2013 |
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Current U.S.
Class: |
404/6 ;
404/72 |
Current CPC
Class: |
E01F 15/146 20130101;
E01F 13/12 20130101; E01F 15/003 20130101 |
International
Class: |
E01F 15/00 20060101
E01F015/00; E01F 15/14 20060101 E01F015/14 |
Claims
1. A bollard system comprising: multiple support beams adapted to
be embedded in concrete; multiple bollards, each bollard being
attached to a support beam a point near a center of the beam; and a
reinforcing bar that is woven between the support beams to provide
reinforcement to the system.
2. The system of claim 1, wherein the support beams are elongated
hollow beams.
3. The system of claim 1, wherein the bollards are elongated pipes
or tubes.
4. The system of claim 1, wherein each bollard is attached to a
support beam near a halfway point along a length of the beam.
5. The system of claim 1, wherein the reinforcing bar is made of
steel.
6. The system of claim 1, wherein the reinforcing bar alternately
passes over and under adjacent support beams in a first direction
that is generally perpendicular to the beams.
7. The system of claim 6, wherein the reinforcing bar also
alternately passes under and over adjacent support beams in a
second direction that is opposite to the first direction
8. The system of claim 6, wherein the reinforcing bar alternately
passes over and under more than two support beams.
9. The system of claim 6, wherein the reinforcing bar forms a
crossover point at which the bar crosses over itself and lobes in
which support beams can be received.
10. The system of claim 6, wherein the reinforcing bar is an
endless bar having no free ends.
11. The system of claim 6, wherein the reinforcing bar has free
ends that form hooks that wrap around the same support beam.
12. The system of claim 6, wherein the system comprises two
reinforcing bars having similar shapes that are used as a pair, the
reinforcing bars alternately passing over and under support beams
in a manner in which they form crossover points at which they cross
over each other and lobes in which support beams can be
received.
13. The system of claim 6, wherein the system includes multiple
reinforcing bars, each bar forming a single crossover point at
which the bar crosses over itself and two lobes in which support
beams can be received, wherein the bars are applied to the support
beams in a manner in which the bars overlap each other.
14. The system of claim 6, wherein the reinforcing bar has free
ends that are attached to the same support beam.
15. A bollard system comprising: multiple horizontal support beams
adapted to be embedded in concrete; multiple vertical bollards
extending upward from the support beams, each bollard being
attached to a beam near a halfway point along a length of the beam;
and a reinforcing bar that is woven between the support beams to
provide reinforcement to the system, wherein the reinforcing bar
alternately passes over and under adjacent beams in a first
direction that is generally perpendicular to the beams.
16. The system of claim 6, wherein the reinforcing bar also
alternately passes under and over adjacent support beams in a
second direction that is opposite to the first direction.
17. The system of claim 6, wherein the reinforcing bar alternately
passes over and under more than two support beams.
18. The system of claim 15, wherein the reinforcing bar forms a
crossover point at which the bar crosses over itself and lobes in
which support beams can be received.
19. The system of claim 15, wherein the system comprises two
reinforcing bars having similar shapes that are used as a pair, the
reinforcing bars alternately passing over and under support beams
in a manner in which they form crossover points at which they cross
over each other and lobes in which support beams can be
received.
20. The system of claim 15, wherein the system includes multiple
reinforcing bars, each bar forming a single crossover point at
which the bar crosses over itself and two lobes in which support
beams can be received, wherein the bars are applied to the support
beams in a manner in which the bars overlap each other.
21. The system of claim 15, wherein the reinforcing bar has free
ends that are attached to the same support beam.
22. A method for supporting bollards, the method comprising:
attaching each bollard to a support beam at a point near a center
of the beam; and weaving a reinforcing bar between the beams to
provide reinforcement, wherein the reinforcing bar alternately
passes over and under adjacent support beams in a first direction
that is generally perpendicular to the beams.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to co-pending U.S.
Provisional Application Ser. No. 61/865,413, filed Aug. 13, 2013,
which is hereby incorporated by reference herein in its
entirety.
BACKGROUND
[0002] Bollards are short vertical posts that are often used to
obstruct the passage of motor vehicles. In conventional systems,
each bollard is attached to a horizontal steel beam that is
embedded in concrete. In systems that comprise multiple bollards,
multiple steel beams are used (one for each bollard), which are
typically parallel to each other. The bollards are attached to the
front ends, i.e., the ends that face vehicle traffic, of the beams.
Steel rebar mats are typically positioned above and below the beams
to reinforce the concrete and limit movement of the beams should a
vehicle impact one or more of the bollards.
[0003] While the above-described systems function adequately well,
these systems are inefficient. When a vehicle impacts a bollard, a
moment is applied to the bollard that, if it were not adequately
supported, would knock it over. The beam and the rebar mat that
lies below the beam are designed to oppose this moment. In order to
achieve this, the beam must be relatively long and thick, and
therefore requires a large amount of steel to construct. The rebar
mats that are provided above and below the beams only add to the
amount of steel that is required to fabricate the system. The large
amount of steel that is required in such systems unnecessarily
increases the costs of the systems.
[0004] From the above discussion, it can be appreciated that it
would be desirable to have systems and methods for supporting
bollards that require less steel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The present disclosure may be better understood with
reference to the following figures. Matching reference numerals
designate corresponding parts throughout the figures, which are not
necessarily drawn to scale.
[0006] FIG. 1A is a perspective view of a first embodiment of a
bollard system.
[0007] FIG. 1B is a schematic end view of support beams and a woven
reinforcement bar of the system of FIG. 1A.
[0008] FIG. 1C is a schematic end view of the woven reinforcement
bar shown in FIG. 1B.
[0009] FIG. 2A is a perspective view of a second embodiment of a
bollard system.
[0010] FIG. 2B is a schematic end view of support beams and a woven
reinforcement bar of the system of FIG. 2A.
[0011] FIG. 2C is a schematic end view of the woven reinforcement
bar shown in FIG. 2B.
[0012] FIG. 3A is a perspective view of a third embodiment of a
bollard system.
[0013] FIG. 3B is a schematic end view of support beams and woven
reinforcement bars of the system of FIG. 3A.
[0014] FIG. 3C is a schematic end view of the woven reinforcement
bars shown in FIG. 3B.
[0015] FIG. 4A is a perspective view of a fourth embodiment of a
bollard system.
[0016] FIG. 4B is a schematic end view of support beams and woven
reinforcement bars of the system of FIG. 4A.
[0017] FIG. 4C is a schematic end view of a woven reinforcement bar
shown in FIG. 4B.
[0018] FIG. 5A is a perspective view of a fifth embodiment of a
bollard system.
[0019] FIG. 5B is a schematic end view of support beams and woven
reinforcement bars of the system of FIG. 5A.
[0020] FIG. 5C is a schematic end view of a woven reinforcement bar
shown in FIG. 5B.
[0021] FIG. 6A is a perspective view of a sixth embodiment of a
bollard system.
[0022] FIG. 6B is a schematic end view of support beams and woven
reinforcement bars of the system of FIG. 6A.
[0023] FIG. 6C is a schematic end view of a woven reinforcement bar
shown in FIG. 6B.
[0024] FIG. 7A is a perspective view of a seventh embodiment of a
bollard system.
[0025] FIG. 7B is a schematic end view of support beams and woven
reinforcement bars of the system of FIG. 7A.
[0026] FIG. 7C is a schematic end view of a woven reinforcement bar
shown in FIG. 7B.
DETAILED DESCRIPTION
[0027] As described above, it would be desirable to have systems
and methods for supporting bollards that require less steel than
conventional systems. Disclosed herein are examples of such systems
and methods. In some embodiments, bollards are attached near the
centers of support beams of the system instead of the front ends of
the beams. When a bollard is struck by an impacting vehicle, the
moment applied to its support beam is resisted by both the front
(compression) end and the rear (tension) end of the beam.
Approximately half of the moment in the bollard will be carried in
each direction and, therefore, the peak load on the beam is cut in
half. Because of this, the beam need not be as robust and therefore
can be made from less material (e.g., steel). In some embodiments,
the support beams are reinforced with reinforcing bars that are
woven between the beams. The advantage of the woven configuration
is that it provides a positive reaction force that resists motion
of each adjacent support beam whether the beam is pushed upward or
downward.
[0028] In the following disclosure, various specific embodiments
are described. It is to be understood that those embodiments are
example implementations of the disclosed inventions and that
alternative embodiments are possible. All such embodiments are
intended to fall within the scope of this disclosure.
[0029] As described above, bollard systems disclosed herein
generally include bollards that are attached near the centers of
support beams that are embedded in an appropriate foundation
material, such as concrete. Also embedded in the material are one
or more reinforcing bars that are woven between the support beams.
Described below are multiple embodiments of bollard systems that
comprise these general features.
[0030] FIG. 1A illustrates a first bollard system 10. As indicated
in this figure, the system 10 includes multiple bollards 12. More
particularly, the illustrated system 10 includes four bollards 12.
While four bollards 12 are shown, if will be appreciated that the
system 10 can include a greater or lesser number of bollards. In
some embodiments, each bollard 12 comprises a relatively short
elongated vertical member that is designed to withstand the forces
associated with an impact from a motor vehicle. By way of example,
the bollards 12 can comprise steel pipes or tubes that may or may
not be filled with concrete.
[0031] Irrespective of its construction, each bollard is attached,
for example, welded, to a single support beam 14 near its center
(i.e., approximately halfway along its length). Because there are
four bollards 12 in the illustrated example, there are four support
beams 14 that together form part of the foundation of the bollard
system 10. In some embodiments, each support beam 14 is a hollow
steel beam having a front end 16, a rear end 18, and a rectangular
cross-section.
[0032] As mentioned above, positioning the bollards 12 near the
centers of the support beams 14 enables the support beams to resist
a moment applied to the bollard using both the front (compression)
end and the rear (tension) end of the beam. Therefore,
approximately half of the moment in the bollard will be carried in
each direction along the beam 14 and the peak load on the beam is
cut in half. Because of this, the support beams 14 can be made from
less material and at less expense.
[0033] It is further noted that rotation of the bollard 12 due to
vehicular impact will raise the front end 16 of its associated
support beam 14. If the bollard 12 rotates as much as 30 degrees
and the bollard and support beam 14 do not form a plastic hinge,
the front end 16 of the beam may be raised several feet out of the
ground. Because the impacting vehicle will be positioned over the
support tube 14 at the beginning of the impact, the front end 16 of
the raised support beam will likely be snagged by the vehicle,
which will deliver high resistance forces without any significant
bending load in the beam. In some embodiments, the front ends 16 of
the support beams 14 can be optimized to increase the snagging
potential and maximize load carrying capacity. For example, the top
edges of the front ends 16 can be stiffened and sharpened in order
to reduce the size of the snag point needed to engage the beam.
[0034] Woven between at least the front ends 16 of the support
beams 14 is a reinforcing bar 20. Notably, a similar reinforcing
bar 20 is also woven between the rear ends 18 of the support beams
14. The reinforcing bar 20 is described herein as being "woven"
between the beams 14 because it alternately passes over and under
adjacent beams in a first direction generally perpendicular and
then under and over the same beams in a second direction opposite
to the first direction so as to tie the beams together in similar
manner to the way in which warp yarns tie together weft yarns in a
woven textile. As shown in FIGS. 1B and 1C, the repeated passing
over and under the beams 14 in the two directions creates multiple
crossover points 22 at which the reinforcing bar crosses over
itself and open lobes 24 between the crossover points in which a
support beam 14 can be secured. This configuration of the
reinforcing bar 20 provides a positive reaction force that resists
motion of the beams 14 whether they are pushed up or down. This
enables the bollards 12 to be moved from the front ends of the
support beams 14 to the centers of the beams, as illustrated in
FIG. 1A.
[0035] FIG. 1B schematically illustrates the weaving of the
reinforcing bar 20 through the support beams 14. In some
embodiments, the reinforcing bar 20 is made of steel rebar. In the
example of FIG. 1, the reinforcing bar 20 comprises a single,
endless bar that forms a continuous woven loop that wraps around
the beams 14. FIG. 1C shows the reinforcing bar 20 without the
presence of the beams 14.
[0036] During construction of the bollard system 10, the support
beams 14 and their associated bollards 12 can be positioned at the
installation site in the desired locations in an orientation
similar to that shown in FIG. 1A. A reinforcing bar 20 can be
passed over at least the front ends 16 of the beams 14 and
potentially the rear ends 18 of the beams. Once the reinforcing
bar(s) 20 is in place, concrete can be poured over the beams 14 and
the reinforcing bar(s) 20.
[0037] FIGS. 2-7 illustrate alternative bollard systems. In each of
these systems, the bollards and the support beams have the same
reference numerals and can be assumed to have similar
configurations to those described above in relation to FIG. 1. The
primary differences between each of the embodiments is the
reinforcing bars that are used to reinforce the systems. Therefore,
the discussions of FIGS. 2-7 that follow focus on the
configurations of the reinforcing bars.
[0038] Turning to FIG. 2A, a bollard system 30 includes bollards 12
that are attached near the centers of support beams 14. Woven
between at least the front ends 16 of the beams 14 is a reinforcing
bar 32. The reinforcing bar 32 can have a construction similar to
that of the reinforcing bar 20 shown in FIG. 1. Therefore, the
reinforcing bar can be made of steel rebar. In the embodiment of
FIG. 2, however, the reinforcing bar 32 is not endless and
therefore has free ends 34 and 36. In the illustrated example, the
free ends 34, 36 form hooks that wrap around one of the beams 14
(the leftmost beam in FIGS. 2A and 2B). As shown most clearly in
FIGS. 2B and 2C, the lengths of the reinforcing bar 32 forming
these hooks form an overlapping region in which the lengths run
parallel to each other. This overlap provides resistance to tensile
forces in the circumstance of a vehicle impacting one of the
bollards 14. The amount of overlap may vary depending upon the
application. As before, the weaving of the reinforcing bar 32
between the breams 14 creates multiple crossover points 38 between
which are open lobes 40 in which the beams 14 can be secured.
[0039] Referring next to FIG. 3A, a bollard system 50 includes
bollards 12 that are attached near the centers of support beams 14.
Woven between at least the front ends 16 of the beams 14 are two
reinforcing bars 52 and 54. The reinforcing bars 52, 54 can each
have a construction similar to that of the reinforcing bar 20 shown
in FIG. 1. As is shown most clearly in FIG. 3C, however, each
reinforcing bar 52, 54 has a generally sinusoidal shape so that,
when the bars are inverted relative to each other as indicated in
FIG. 3C, they together form a weaving pattern similar to that
formed by the single reinforcing bars 20 and 32 of FIGS. 1 and 2
(see FIG. 3B). Described another way, if both bars 52, 54 are
considered to trace the general shape of a sine wave, the two bars
can be oriented such that the waves are 180.degree. out of phase
with each other. As is apparent from FIG. 3B, this results multiple
crossover points 56 between which are open lobes 58 in which the
support beam 14 can be secured.
[0040] The first reinforcing bar 52 has first and second free ends
60 and 62, respectively, and the second reinforcing bar 54 has
first and second free ends 64 and 66, respectively. In similar
manner to the free ends 34, 36 of the embodiment of FIG. 2, the
first free ends 60, 64 of the bars 52, 54 form hooks that wrap
around one of the beams 14 (the leftmost beam in FIGS. 3A and 3B)
and create an overlapping region in which the ends run parallel to
each other. In addition, the second free ends 62, 66 of the bars
52, 54 form hooks that wrap around another of the beams 14 (the
rightmost beam in FIGS. 3A and 3B) and create an overlapping region
in which the ends run parallel to each other. As before, the
overlapping regions provide resistance to tensile forces.
[0041] With reference next to FIG. 4A, a bollard system 70 includes
bollards 12 that are attached near the centers of support beams 14.
Woven between at least the front ends 16 of the beams 14 are
multiple reinforcing bars 72. More particularly, there are three
reinforcing bars 72 woven between the beams 14 because there are
four such beams to be reinforced. The reinforcing bars 72 can each
have a construction similar to that of the reinforcing bar 20 shown
in FIG. 1. Like the reinforcing bar 20, the reinforcing bars 72
each comprise an endless bar that can be passed over the beams 14.
However, unlike the reinforcing bar 20, the reinforcing bars 72 are
each only configured to wrap around two adjacent support beams 14.
As is illustrated most clearly in FIG. 4C, each reinforcing bar 72
forms a single crossover point 74 so as to form and endless curve
having two lobes 76. This curve can be described as a "figure-8"
shape. Although the reinforcing bars 72 do not weave individually
between each of the beams as in previously described embodiments,
the same result occurs because, as shown in FIG. 4A, the
reinforcing bars 72 overlap each other. More particularly, the
lobes 76 of adjacent reinforcing bars 72 overlap multiple beams 14
and each other across the foundation. As can be appreciated from
FIG. 4A, in order to achieve this overlap, each reinforcing bar 72
can be angled relative to the support beams 14 (i.e., so they are
not exactly perpendicular to the beams) to make space for two lobes
76 on individual beams.
[0042] Referring next to FIG. 5A, a bollard system 80 includes
bollards 12 that are attached near the centers of support beams 14.
Woven between at least the front ends 16 of the beams 14 are
multiple reinforcing bars 82. More particularly, there are three
reinforcing bars 82 because there are four support beams 14 to be
reinforced. The reinforcing bars 82 share similarities with both
the reinforcing bar 32 of FIG. 2 and the reinforcing bars 72 of
FIG. 4. In particular, the reinforcing bars 82 each have free ends
88 and 90 that form hooks that wrap around a beam 14 (see FIG. 5B)
like the reinforcing bar 32. In addition, the reinforcing bars 82
each form a "figure-8 shape" having a single crossover point 92 and
two lobes 94 (see FIG. 5C) like the reinforcing bars 72. As can be
appreciated from FIG. 5A, in order to achieve this overlap, each
reinforcing bar 82 is angled relative to the support beams 14 to
make space for two lobes 94 on individual beams.
[0043] Turning to FIG. 6, a bollard system 100 includes bollards 12
that are attached near the centers of support beams 14. Woven
between at least the front ends 16 of the beams 14 are multiple
pairs of reinforcing bars 102 and 104, three pairs being provided
reinforce tie the four support beams. Individually, each
reinforcing bar 102, 104 forms an S-shape, which can be seen most
clearly in FIG. 6C. However, when the reinforcing bars 102, 104 are
inverted relative to each other as in FIG. 4C and paired together
as in FIG. 6B, they each form a figure-8 shape having a single
crossover point 106 and two lobes 108 (see FIG. 6C) like the
reinforcing bars 72. Similar to the reinforcing bars 52, 54 shown
in FIG. 3, the first reinforcing bar 102 has first and second free
ends 110 and 112, respectively, and the second reinforcing bar 104
has first and second free ends 114 and 116, respectively. The first
free ends 110, 114 of the bars 102, 104 form hooks that wrap around
one of the beams 14 and the second free ends 112, 116 of the bars
form hooks that wrap around another of the beams 14 to form
overlapping regions at each of the beams. As can be appreciated
from FIG. 6A, the pairs of reinforcing bars 102, 104 can be angled
relative to the support beams 14 to make space for two lobes 108 on
individual beams.
[0044] FIG. 7 illustrates a further bollard system 120 that
includes bollards 12 that are attached near the centers of support
beams 14. Woven between at least the front ends 16 of the beams 14
are multiple reinforcing bars 122. More particularly, there are
three reinforcing bars 122 because there are four support beams 14
to be reinforced. The reinforcing bars 122 are similar to the
reinforcing bars 82 shown in FIG. 5 because they each comprise a
single bar that forms a figure-8 shape having a single crossover
point 124, two lobes 126, and two free ends 128 and 130. Unlike the
reinforcing bars 82, however, the free ends 128, 130, do not form
hooks that wrap around a support beam 14. Instead, the free ends
128, 130 are attached (e.g., welded) to the top and bottom of the
support beam 14, respectively. Because of this, there is no need to
form an overlap between the two free ends 128, 130. In some
embodiments, a reinforcing bar 122 can be attached to each support
beam 14 of the system 130 except for the last beam (the rightmost
beam in the example of FIG. 7A) prior to shipping the system 120 to
the installation site. In such a case, assembly of the system 130
is simplified. As can be appreciated from FIG. 7A, each reinforcing
bar 122 can be angled relative to the support beams 14 to make
space for two lobes 126 on individual beams.
* * * * *